Answer:
They used 3.14 for pi:


Step-by-step explanation:
is the volume of a sphere with radius r.
I think that is the diameter given in the picture.
The radius is half the diameter.
So the radius is 5 since the diameter is 10.
Plug in this gives you:

Answer:
John answered 50 questions.
Step-by-step explanation:
Although five of John's answers were incorrect, 90% of his answers were correct.
This means that 5 is 100 - 90% = 10% of the total number of questions, n. So



John answered 50 questions.
That any number plus 0 is equal to the number itself.
Answer:
PD = 8
Step-by-step explanation:
PC x PD = PA x PB
3 x PD = 4 x (4 + 2)
3PD = 24
PD = 8